Popliteal Artery Entrapment

Section Editor: James S.T. Yao

Popliteal Artery Entrapment with Structural Damage

by: James S.T. Yao
Northwestern University Medical School
Chicago, Illinois

Brief Case History

In young claudicants with decreased or absent pedal pulses, popliteal artery entrapment should be suspected. Thrombosis of the popliteal artery is known to occur and, occasionally, aneurysm formation may also be encountered. Computed axial tomography (CT) or magnetic resonance imaging (MRI) provides precise anatomical display of muscle structure of the popliteal fossa and is highly diagnostic for entrapment even when the artery is occluded. (Figure 1) CT is also helpful to detect aneurysm formation. (Figure 2) Arteriogram confirms the diagnosis and is helpful to assess the extent of the damage. (Figure 3) Arteriogram often demonstrates occluded popliteal artery with normal smooth proximal artery and the presence of large collateral artery. (Figure 4)

Aneurysm formation is uncommon but has been reported. Figure 5 shows an operative photograph of the patient in Figure 2 where a small aneurysm was found below the abnormal muscle-fibrous band. In the presence of structural damage of the popliteal artery such as aneurysm or occlusion, a short interposed vein graft is needed to restore continuity.

Figure 1: CT scan in a patient with thrombosis of the left popliteal artery (small arrow). Anomalous origin of medial head of the left gastrocnemius muscle (large arrow) was clearly demonstrated, in contrast to normal anatomic relationship seen in the right popliteal fossa.

Figure 2: CT scan showing a left popliteal aneurysm.

Figure 3 : Arteriogram in the same patient in Figure 2. Note a small focal aneurysmal dilatation of the popliteal artery. The rest of the arterial tree appears to be normal without wall irregularity.

Figure 4: Arteriogram in a patient with short segmental occlusion of the right popliteal artery due to entrapment. Note the smooth appearance of the proximal and distal arteries.

Figure 5: Operative photograph of the same patient as in Figures 2 and 3 demonstrating an aneurysm below the abnormal muscle band.

| Top of Page

Society for Vascular Surgery - 633 N. St. Clair, 24th Floor; Chicago, IL 60611; Phone: 312-334-2300 or 800-258-7188; Fax: 312-334-2320; Email: vascular@vascularsociety.org
© 2009 VascularWeb. All rights reserved. Use of the VascularWeb site constitutes acceptance of all of the policies, rules and regulations for the site.